Hottest temperature on Earth revised

The hottest temperature recorded on Earth is not as hot as previously thought, after the World Meteorological Organisation declared the phenomenal 58C recorded in Libya 90 years ago was wrong.

Instead, the sizzling title goes to Death Valley, California, where in July 1913, a top temperature of 56.7C was recorded.

That compares to Australia's highest recorded temperature of 50.7C, recorded in Oodnadatta, South Australia in January 1960.

The revised pecking order emerged after a panel of climate experts reviewed the method employed to take the temperature in El Azizia, southwest of the Libyan capital Tripoli in 1922.

The experts concluded that the thermometer used was not standard and determined that the person who measured the temperature was probably inexperienced.

"We're pretty sure that the person who was tasked with taking the measurements using this instrument didn't know how to use it," said Randy Cerveny, who headed the World Meteorological Organisation project.

An expert on climate extremes, Mr Cerveny said the original 1922 logbook had data recorded in the wrong columns which reflected a degree of inexperience.

He theorised that the unidentified individual had in fact completely misread the thermometer "and was off by five degrees Celsius".

It's not unusual for records to be reviewed. Climatologist at the Bureau of Meteorology Dr Blair Trewin said not all readings survived scrutiny.

Among the more famous not to make the record books was the 53C temperature taken in Cloncurry, in north-west Queensland, in 1889.

"We found documentary evidence for that which showed the measurement was taken in — would you believe — a beer crate nailed to the side of a house," he said. "That would certainly have affected the reading ... which was probably somewhere around 47C."

In Australia, standard screens used to cover thermometers in the field came in progressively between 1890-1910.

Dr Trewin said the record books only contained readings taken in these screens, as they standardised the equipment. Regular reviews are still undertaken though, as instrument faults or clerical errors can still occur.

After Oodnadatta the next hottest recorded places in Australia are Mardie in Western Australia (50.5C in February 1998), Menindee in New South Wales (49.7C in January 1939), Birdsville in Queensland (49.5C in December 1972) and Hopetoun in Victoria (48.8C in February 2009).

The coldest recorded place is Charlotte Pass in NSW, where the mercury plunged to -23 in June 1994. The next coldest places — all tied at -13C — are all in Tasmania: Butlers Gorge, Shannon and Tarraleah. Omeo in Victoria recorded an icy -11.7 in June 1965, as did Falls Creek in July 1970.